Uzbekistan, being historically one of the most populated and agriculture-based republics in the former Soviet Union, still features quite high annual population growth rates and great dependence on agriculture as a backbone for the rest of the economic reforms. With water playing an extremely important role in producing a sufficient food base for the country's growing population and earning much needed foreign exchange for the government to ensure overall economic development, the pressures on this scarce resource will obviously and inevitably grow, putting it much at risk over a long-term perspective. So would available water be enough to meet ever-increasing demands from major economic uses in the foreseeable future, and what can be the options for meeting such demands - these are the key questions raised and researched in this article. As such the research concentrates on the two major country-specific scenarios with water and its multiple uses for Uzbekistan - the business as usual and the best case. Both scenarios discuss possible future implications for the next quarter-century given certain assumptions. Finally when summarizing the findings, the paper provides conclusions and recommendations as to how the model and further scenarios can be better optimized given the trans-boundary nature of most water resources in Central Asia where Uzbekistan geographically belongs.

Uzbekistan, being historically one of the most populated and agriculture-based republics in the former Soviet Union, still features quite high annual population growth rates and great dependence on agriculture as a backbone for the rest of the economic reforms.With water playing an extremely important role in producing a sufficient food base for the country's growing population and earning much needed foreign exchange for the government to ensure overall economic development, the pressures on this scarce resource will obviously and inevitably grow, putting it much at risk over a long-term perspective. So would available water be enough to meet ever-increasing demands from major economic uses in the foreseeable future, and what can be the options for meeting such demands - these are the key questions raised and researched in this article. As such the research concentrates on the two major country-specific scenarios with water and its multiple uses for Uzbekistan - the business as usual and the best case. Both scenarios discuss possible future implications for the next quarter-century given certain assumptions. Finally when summarizing the findings, the paper provides conclusions and recommendations as to how the model and further scenarios can be better optimized given the trans-boundary nature of most water resources in Central Asia where Uzbekistan geographically belongs.

This article examines impacts of infrastructure development and climate variability on economic outcomes for the Amu Darya Basin in Central Asia. It aims to identify the most economically productive mix of expanded reservoir storage for economic benefit sharing to occur, in which economic welfare of all riparians is improved. Policies examined include four combinations of storage infrastructure for each of two climate futures. An empirical optimization model is developed and applied to identify opportunities for improving the welfare of Tajikistan, Uzbekistan, Afghanistan, and Turkmenistan. The analysis 1) characterizes politically constrained and economically optimized water-use patterns for these combinations of expanded reservoir storage capacity, 2) describes Pareto-Improving packages of expanded storage capacity that could raise economic welfare for all four riparians, and accounts for impacts for each of two climate scenarios. Results indicate that a combination of targeted water storage infrastructure and efficient water allocation could produce outcomes for which the discounted net present value of benefits are favorable for each riparian. Results identify a framework to provide economic motivation for all riparians to cooperate through development of water storage infrastructure. Our findings illustrate the principle that development of water infrastructure can expand the negotiation space by which all communities can gain economic benefits in the face of limited water supply. Still, despite our optimistic findings, patient and deliberate negotiation will be required to transform potential improvements into actual gains.

Assessing future water requirements for feeding the growing population of Central Asia can improve understanding of the projected water supply scenarios in the region. Future water requirements will be partially determined by the dietary habits of the populations, and are thus responsive to significant variation of income levels. Using Uzbekistan as an example, this study projects the water footprints of income driven changes on the population's diet in Central Asia. To reveal the influence of large income changes on dietary habits a Normalized Quadratic-Quadratic Expenditure System was calibrated and applied to data from 2009. The national water footprints of food consumption in Uzbekistan were projected until 2034 by applying the parameterized demand system to estimate the respective water footprint values. The results showed that for Uzbekistan the projected increase in the food consumption water footprint would be primarily linked to income growth rather than population growth. Due to the high water footprint of common food products, the composition of the population’s diet, and responsiveness to income, economic growth is expected to put greater pressure on water resources in Uzbekistan unless proper measures are undertaken.

According to the UN, the population of Central Asia will increase from its current approximately 65million people to a well over 90million by the end of this century. Taking this increasing population into consideration, it is impossible to project development strategies without considering three key factors in meeting the demands of a growing population: water, food and energy. Societies will have to choose, for instance, between using land and fertilizer for food production or for bio-based or renewable energy production, and between using fresh water for energy production or for irrigating crops. Thus water, food and energy are inextricably linked and must be considered together as a system. Recently, tensions among the Central Asian countries over the use of water for energy and energy production have increased with the building of Rogun Dam on the Vakhsh River, a tributary of the Amu Darya River. The dam will provide upstream Tajikistan with hydropower, while downstream countries fear it could negatively impact their irrigated agriculture. Despite recent peer reviewed literature on water resources management in Amu Darya Basin, none to date have addressed the interconnection and mutual impacts within water–energy–food systems in face of constructing the Rogun Dam. We examine two potential operation modes of the dam: Energy Mode (ensuring Tajikistan’s hydropower needs) and Irrigation Mode (ensuring water for agriculture downstream). Results show that the Energy Mode could ensure more than double Tajikistan’s energy capacity, but would reduce water availability during the growing season, resulting in an average 37% decline in agricultural benefits in downstream countries. The Irrigation Mode could bring a surplus in agricultural benefits to Tajikistan and Uzbekistan in addition an increasing energy benefits in Tajikistan by two fold. However, energy production in the Irrigation Mode would be non-optimally distributed over the seasons resulting in the most of hydropower being produced during the growing season. Neither operation mode provides optimal benefits for all the countries, emphasizing how difficult it is to actually reach a win–win scenario across the water–energy–food security nexus in transboundary river basins.

Vicious competition for limited water resources hinders the synergetic and sustainable development of Central Asian countries, which further threatens food security and exacerbates ecological degradation. In this study, a copula-based bi-level decentralized programming (CBDP) method is developed and applied to planning water-food-ecology (WFE) nexus system. CBDP has advantages in balancing tradeoffs between different decision levels, analyzing synergies among multiple managers and reflecting joint risks of interrelated uncertain parameters. Then, a CBDP-WFE model is formulated for Central Asia, where the upper-level model aims to maximize system benefit for the region (i.e. regional-scale), and the lower-level model involves five objectives to maximize five countries’ benefits (i.e. national-scale) respectively. Totally 108 scenarios are designed to analyze the impacts of joint constraint-violation risk, agricultural irrigation efficiency, and ecological water demand. Results reveal that (i) improving agricultural irrigation efficiency can optimize the water allocation pattern as well as increase the system benefit; (ii) in order to restore the regional eco-environment, the proportion of ecological water allocation should increase from 7% (of the current level) to 14.9–23.8% (by 2050); (iii) water allocations to Uzbekistan and Tajikistan should be properly controlled especially when available water is scarce. The results are helpful for managers in not only making decisions of water allocation among multiple users and countries but also gaining insight into synergetic management of WFE nexus under various system conditions.

The water-energy-food (WEF) nexus is a holistic concept used to understand the synergies and trade-offs of interdependent water, energy, and food resources. Despite its widespread use, this concept often overlooks environmental concerns. In addition, the lack of a systemic approach in the Aral Sea Basin (ASB) has resulted in serious environmental degradation. For instance, the Aral Sea, situated at the terminus of the basin, is steadily shrinking, yet researchers studying the WEF nexus tend to overlook the upstream tributaries of the basin. This study aims to determine the extent to which research on the WEF nexus in the ASB in Central Asia has considered the environment through a systematic review of the literature published between 2012 and 2022. The results indicate that the number of WEF publications regarding the ASB has seen an upward trend, with a primary focus on the transboundary level and less research available on the local and national levels. This confirms the strong reliance of Central Asian states on one another for food, energy, and water resources. Furthermore, the results show that the majority of published studies either do not consider environmental concerns in their analyses at all or do so with little precision. Therefore, to achieve precise and sustainable outcomes, this study recommends the inclusion of environmental concerns along with basin-wide coverage in future WEF analyses. Finally, the WEF concept should be downscaled to the national and local levels in order to facilitate its implementation.

The water-energy-food (WEF) nexus is a holistic concept used to understand the synergies and trade-offs of interdependent water, energy, and food resources. Despite its widespread use, this concept often overlooks environmental concerns. In addition, the lack of a systemic approach in the Aral Sea Basin (ASB) has resulted in serious environmental degradation. For instance, the Aral Sea, situated at the terminus of the basin, is steadily shrinking, yet researchers studying the WEF nexus tend to overlook the upstream tributaries of the basin. This study aims to determine the extent to which research on the WEF nexus in the ASB in Central Asia has considered the environment through a systematic review of the literature published between 2012 and 2022. The results indicate that the number of WEF publications regarding the ASB has seen an upward trend, with a primary focus on the transboundary level and less research available on the local and national levels. This confirms the strong reliance of Central Asian states on one another for food, energy, and water resources. Furthermore, the results show that the majority of published studies either do not consider environmental concerns in their analyses at all or do so with little precision. Therefore, to achieve precise and sustainable outcomes, this study recommends the inclusion of environmental concerns along with basin-wide coverage in future WEF analyses. Finally, the WEF concept should be downscaled to the national and local levels in order to facilitate its implementation.

The widespread uncertainty regarding future changes in climate, socioeconomic conditions, and population growth have increased interest in water-energy-food-ecology nexus-based frameworks in relation to the analysis of water resources. A challenge for modeling the water-energy-food-ecology nexus is how to reduce the multidimensional and codependent uncertainties and measure the complicated casual relationships effectively. We propose a methodological solution to the problem, and this solution is demonstrated in this case as an extension to the previous water resource optimization framework. We coupled the water-energy-food-ecology nexus into the Bayesian network, which provides a formal representation of the joint probabilistic behavior of the system, and the method was applied to water resource use analysis and management in the Syr Darya River basin, a transboundary and endorheic basin that has contributed to the Aral Sea ecological crisis as a result of unreasonable water use. The annual scale data of four periods, 1970–1980, 1980–1991, 1991–2005, and 2005–2015, were introduced into the Bayesian network. Before the disintegration of the Soviet Union, the amount of water inflow into the Aral Sea was sensitive to increases in irrigation for agricultural development, increases in water storage of the upstream reservoirs and stochastic runoff. After the disintegration of the Soviet Union, the amount of water inflow into the Aral Sea was sensitive to the inefficient irrigation water use in the downstream areas of Uzbekistan and Kazakhstan and the water storage of the reservoir located upstream of Kyrgyzstan. The change resulted from unresolvable disputes between water use for power generation in the upstream area and irrigation in the downstream area. Comprehensive scenario analysis shows that, in the short term, it would be useful to improve the proportion of food crops, improve the efficiency of water use in relation to salt leaching and irrigation, and prevent drought damage. In the long term, based on the increased use of advanced drip irrigation technology from 50% to 80%, the annual inflow into the Aral Sea will increase significantly, reaching 6.4 km³ and 9.6 km³, respectively, and this technology is capable of ameliorating the ecological crisis within the basin.

In the inner Aral Sea Basin of Central Asia, numerous small lakes scattered over the irrigated landscape supply diverse ecosystem services for humans and nature. This study aimed to estimate the water volumes and assess the potentials of these small lakes for instance as irrigation reserve during the ever-recurring periods of water scarcity in the ecologically endangered Amudarya Delta. Bathymetric measurements gathered in the Khorezm region, Northwest Uzbekistan, permitted developing a statistical relationship between the surface and volume of the lakes. Landsat satellite data enabled for classifying the water bodies and hence deriving lake volumes over the study area. In 2002, the lakes stored ~0.032 km³ water during the winter season, but ~0.057 km³ during the main, 5–6 months spanning irrigation period. The area-wide increase in lake volumes during the irrigation period underlined the magnitude to which the currently practiced, inefficient use of irrigation water, produces excess water that in turn contributes to the existence of the small, mesotrophic lakes. Based on crop water requirements, calculations showed that the reuse of lake water may compensate for water-scarce situations, albeit to a certain extend only. An increased share (13 % above average) of water-intensive rice fields in the vicinity of the lakes substantiated that some lakes are already used in this way. It is argued that, in case of sufficient water quality, as indicated by other studies, more targeted exploration of such lake water can help simultaneously both, increasing food and water security of the households surrounding the lakes and safeguarding a supply to maintain different ecosystem functions. Integrated management of all water resources may reduce excess irrigation water supply to the region, which in turn may lessen the dependency of Central Asian downstream countries on transboundary water and supply water resources for the ecosystems in the river deltas.